Is co-sleeping really helping your sleep?
The truth is, no.
Research clearly shows that sleep fragmentation produces the same symptoms of sleep deprivation as total sleep deprivation.
Sleep fragmentation happens when we experience many short awakenings during sleep. Sleep deprivation is the feature characteristic of sleep maintenance insomnia, which results from poor sleep-maintenance or poor sleep hygiene.
But won’t I be sleep deprived worse than if I get up out of my bed to attend to my baby at night?
Nope. The results are the same either way, except your child will be in less danger of accidental suffocation, or strangulation, if in a safer sleep environment than in bed with you.
Your baby and toddler’s sleep cycles are 30-50 minutes long. Yours are 90 minutes long. If you are sleeping with your baby, their transition from one sleep cycle to the next, which is active and audible, even loud (moving, kicking, babbling, crying for1-5 minutes), is happening up to three times within your 90-minute cycle, fragmenting your sleep each time.
When sleep is fragmented, it prevents us from receiving the restorative benefits of sleep. Especially when it interrupts or prevents stage 3 and 4 sleep (the deepest and most restorative stages of our sleep cycles).
After only two days of fragmented sleep, the negative affects to our mental health and cognitive function are severely compromised, thus adversely affecting our attunement and parenting responses with our child the following day, not to mention our relationship with our child’s other parent, and other members of the child’s household, creating a less than happy and healthy home.
We also engage in higher risk behaviors, such as getting behind the wheel of a car with our baby in tow. Sleep deprivation impairs driving just as alcohol consumption beyond the legal limit.
I chose not to consume alcohol when my four kids were young, for fear my response time and serve and return responses to their needs would be delayed or inappropriate.
Twenty-one years ago, after being told by my breastfeeding group that I would get more sleep if I co-slept, and also allowing my baby to breastfeed at will throughout the night, I thought I had finally found relief. But, after several months of this, I had accumulated such a tremendous sleep debt from all of the fragmented sleep that one night my exhaustion caused such a sleep crash that I woke to find my daughter nearly suffocating from the position I was in laying next to her. It scared me far more than the months of the miserable depressed and irritable state I was always in during the day.
In fact, my sleep deprivation was so great; I could not discern how bad it was. I also was unable to recognize how chronically sleep deprived my daughter was. Similar to alcohol consumption, we don’t realize our impairment from it and think we are okay to get behind the wheel of a car after a few drinks. Sleep deprivation dulls the senses as well as reaction times, just as alcohol does. 
A dear mom-mentor of mine that I confided in asked me if I would ever leave my baby with her if she was casually drinking throughout the day. My answer was, of course not! Along with nearly suffocating my child, that wise and powerful question sobered me up from the emotional conditioning I had yielded to in my compromised state, from the well-meaning theories of Dr. Sears and my lactation gurus thinking that co-sleeping was safe and healthy. 
The failure to help our little ones in the second stage of infancy and beyond to consolidate their sleep, fostering independent connections from one sleep cycle to the next, puts them at risk in some part, to sleep disorders, among other physical and mental health issues in early childhood. Sleep fragmentation means lower overall sleep duration and quality, which is particularly worrisome in children whose brains are growing and developing at rapid rates, tripling in size and ability from birth to age 3.
My great love for my child coupled with my protective mom-instincts snapped me out of my sleepless fog and denial. Armed with knowledge in pediatric sleep hygiene I created a plan that not only helped my daughter and I experience better quality sleep, but safer sleep, while still protecting positive breastfeeding behaviors and the deep attachment we shared.
I learned then, and with 3 subsequent children, that unhealthy, fragmented sleep was the adversary of attachment, and in conflict with the theory of better sleep via breastfeeding on demand all night, past the biological need for calories around the clock. I remember in my desperation for sleep, I actually compromised my child’s benefits from exclusive breast milk, by offering formula and almost quitting breastfeeding altogether! I learned that protecting my family’s sleep health and safety was the foundation for overall wellness in my children’s lives and home.
 Volkovich, E., Ben-Zion, H., Karny, D., Meiri, G., & Tikotzky, L. (2015, November). Sleep patterns of co-sleeping and solitary sleeping infants and mothers: a longitudinal study. Sleep Medicine, 16(11), 1305-1312.
Written by Jenni June, Certified Child and Family Sleep Consultant, Lactation Counselor, and mom of 4 amazing young adults!